So, I just used JavaScript to re-write the login/logout links. Maybe not the best way, but it works.

<?php
add_action( 'wp_head', function () { ?>
<script>
jQuery(document).ready(function(){
//Rewrite login links
jQuery('a[href*="?foro=signin"]').attr('href', '<?php echo wp_login_url( get_permalink() ); ?>');

//Rewrite logout links
jQuery('a[href*="?foro=logout"]').attr('href', '<?php echo wp_logout_url( get_permalink() ); ?>');

//Remove register links
jQuery('a[href*="?foro=signup"]').remove();
});
</script>
<?php } );